Crashworthiness design methodologies combine crash simulation and design methodology in order to design structures in vehicles. A crashworthiness design requires the modeling of complex interactions between components of the vehicles in a crash event. The design of the structures must also accommodate various conflicting criteria such as limiting the maximum acceleration to avoid injuries to and limiting the maximum deformation to avoid injuries attributable to deformed structures penetrating a passenger cabin. Further, the crashworthiness design often requires designing the structures so that the structures absorb as much energy as possible while deforming in a manner that does not cause injury the passengers.
Most commercial software products for designing structures assume that only elastic deformation takes place in the structures. Further, it is assumed that a load is applied to the structures over a long period of time, which results in a steady-state response from the structures. These assumptions, however, become unrealistic for crash events where loads to the structure and boundary conditions change as time progresses. Accordingly, most commercial software products are incapable of performing crashworthiness designing.
Gradient-based method is one of the techniques used in the crashworthiness design. The gradient-based method, however, requires a nonlinear dynamic finite element analysis that is computationally intensive. Therefore, the gradient-based method takes a very long time to design and evaluate the structures. One way to reduce the computation is to simplify the finite element analysis (FEA). But simplifying the finite element analysis will sacrifice the accuracy and reliability of the crashworthiness design.